dom/base/Link.h

   1 /* -*- Mode: C++; tab-width: 8; indent-tabs-mode: nil; c-basic-offset: 2 -*- */
   2 /* vim: set ts=8 sts=2 et sw=2 tw=80: */
   3 /* This Source Code Form is subject to the terms of the Mozilla Public
   4  * License, v. 2.0. If a copy of the MPL was not distributed with this
   5  * file, You can obtain one at http://mozilla.org/MPL/2.0/. */
   6
   7 /**
   8  * This is the base class for all link classes.
   9  */
  10
  11 #ifndef mozilla_dom_Link_h__
  12 #define mozilla_dom_Link_h__
  13
  14 #include "nsWrapperCache.h" // For nsWrapperCache::FlagsType
  15 #include "nsCOMPtr.h"
  16
  17 class nsIURI;
  18
  19 namespace mozilla {
  20
  21 class EventStates;
  22 class SizeOfState;
  23
  24 namespace dom {
  25
  26 class Document;
  27 class Element;
  28
  29 #define MOZILLA_DOM_LINK_IMPLEMENTATION_IID          \
  30   {                                                  \
  31     0xb25edee6, 0xdd35, 0x4f8b, {                    \
  32       0xab, 0x90, 0x66, 0xd0, 0xbd, 0x3c, 0x22, 0xd5 \
  33     }                                                \
  34   }
  35
  36 class Link : public nsISupports {
  37  public:
  38   NS_DECLARE_STATIC_IID_ACCESSOR(MOZILLA_DOM_LINK_IMPLEMENTATION_IID)
  39
  40   /**
  41    * aElement is the element pointer corresponding to this link.
  42    */
  43   explicit Link(Element* aElement);
  44
  45   /**
  46    * This constructor is only used for testing.
  47    */
  48   explicit Link();
  49
  50   virtual void VisitedQueryFinished(bool aVisited);
  51
  52   /**
  53    * @return NS_EVENT_STATE_VISITED if this link is visited,
  54    *         NS_EVENT_STATE_UNVISTED if this link is not visited, or 0 if this
  55    *         link is not actually a link.
  56    */
  57   EventStates LinkState() const;
  58
  59   /**
  60    * @return the URI this link is for, if available.
  61    */
  62   nsIURI* GetURI() const;
  63
  64   /**
  65    * Helper methods for modifying and obtaining parts of the URI of the Link.
  66    */
  67   void SetProtocol(const nsAString& aProtocol);
  68   void SetUsername(const nsAString& aUsername);
  69   void SetPassword(const nsAString& aPassword);
  70   void SetHost(const nsAString& aHost);
  71   void SetHostname(const nsAString& aHostname);
  72   void SetPathname(const nsAString& aPathname);
  73   void SetSearch(const nsAString& aSearch);
  74   void SetPort(const nsAString& aPort);
  75   void SetHash(const nsAString& aHash);
  76   void GetOrigin(nsAString& aOrigin);
  77   void GetProtocol(nsAString& _protocol);
  78   void GetUsername(nsAString& aUsername);
  79   void GetPassword(nsAString& aPassword);
  80   void GetHost(nsAString& _host);
  81   void GetHostname(nsAString& _hostname);
  82   void GetPathname(nsAString& _pathname);
  83   void GetSearch(nsAString& _search);
  84   void GetPort(nsAString& _port);
  85   void GetHash(nsAString& _hash);
  86
  87   /**
  88    * Invalidates any link caching, and resets the state to the default.
  89    *
  90    * @param aNotify
  91    *        true if ResetLinkState should notify the owning document about style
  92    *        changes or false if it should not.
  93    */
  94   void ResetLinkState(bool aNotify, bool aHasHref);
  95
  96   // This method nevers returns a null element.
  97   Element* GetElement() const { return mElement; }
  98
  99   /**
 100    * DNS prefetch has been deferred until later, e.g. page load complete.
 101    */
 102   virtual void OnDNSPrefetchDeferred() { /*do nothing*/
 103   }
 104
 105   /**
 106    * DNS prefetch has been submitted to Host Resolver.
 107    */
 108   virtual void OnDNSPrefetchRequested() { /*do nothing*/
 109   }
 110
 111   /**
 112    * Checks if DNS Prefetching is ok
 113    *
 114    * @returns boolean
 115    *          Defaults to true; should be overridden for specialised cases
 116    */
 117   virtual bool HasDeferredDNSPrefetchRequest() { return true; }
 118
 119   virtual size_t SizeOfExcludingThis(mozilla::SizeOfState& aState) const;
 120
 121   virtual bool ElementHasHref() const;
 122
 123   // This is called by HTMLAnchorElement and HTMLLinkElement.
 124   void TryDNSPrefetch();
 125   void CancelDNSPrefetch(nsWrapperCache::FlagsType aDeferredFlag,
 126                          nsWrapperCache::FlagsType aRequestedFlag);
 127
 128   bool HasPendingLinkUpdate() const { return mHasPendingLinkUpdate; }
 129   void SetHasPendingLinkUpdate() { mHasPendingLinkUpdate = true; }
 130   void ClearHasPendingLinkUpdate() { mHasPendingLinkUpdate = false; }
 131
 132   // To ensure correct mHasPendingLinkUpdate handling, we have this method
 133   // similar to the one in Element. Overriders must call
 134   // ClearHasPendingLinkUpdate().
 135   // If you change this, change also the method in nsINode.
 136   virtual void NodeInfoChanged(Document* aOldDoc) = 0;
 137
 138   bool IsInDNSPrefetch() { return mInDNSPrefetch; }
 139   void SetIsInDNSPrefetch() { mInDNSPrefetch = true; }
 140   void ClearIsInDNSPrefetch() { mInDNSPrefetch = false; }
 141
 142  protected:
 143   virtual ~Link();
 144
 145   /**
 146    * Return true if the link has associated URI.
 147    */
 148   bool HasURI() const {
 149     if (HasCachedURI()) {
 150       return true;
 151     }
 152
 153     return !!GetURI();
 154   }
 155
 156   nsIURI* GetCachedURI() const { return mCachedURI; }
 157   bool HasCachedURI() const { return !!mCachedURI; }
 158
 159  private:
 160   /**
 161    * Unregisters from History so this node no longer gets notifications about
 162    * changes to visitedness.
 163    */
 164   void UnregisterFromHistory();
 165
 166   void SetHrefAttribute(nsIURI* aURI);
 167
 168   mutable nsCOMPtr<nsIURI> mCachedURI;
 169
 170   Element* const mElement;
 171
 172   uint16_t mLinkState;
 173
 174   bool mNeedsRegistration : 1;
 175
 176   bool mRegistered : 1;
 177
 178   bool mHasPendingLinkUpdate : 1;
 179
 180   bool mInDNSPrefetch : 1;
 181
 182   bool mHistory : 1;
 183 };
 184
 185 NS_DEFINE_STATIC_IID_ACCESSOR(Link, MOZILLA_DOM_LINK_IMPLEMENTATION_IID)
 186
 187 }  // namespace dom
 188 }  // namespace mozilla
 189
 190 #endif  // mozilla_dom_Link_h__